Along with the recent growth of information processing technology, it is becoming possible to provide a touch panel on the display panel of an information processing device, such as a computer or a mobile information terminal, and operate the information processing device by operating the touch panel with the human body, a stylus pen, or the like.
For example, Patent Literature 1 below discloses a display device provided with a touch panel, and a touch pen, which is an input device for performing input operations on the display device.